Communication system and method for correlating wireless communication performance with vehicle system configurations

ABSTRACT

Systems and methods for correlating wireless communication performance with vehicle system configurations determine wireless message characteristics of wireless messages communicated with vehicles in vehicle systems and locations along a route where the wireless message characteristics were determined. The wireless message characteristics and the locations can be determined during movement of the vehicle systems along a route. Consist configuration information about the one or more vehicle systems is obtained, and a signal propagation profile is determined based on the wireless message characteristics, the locations where the wireless message characteristics were determined, and the consist configuration information. The signal propagation profile can represent one or more relationships between the wireless message characteristics, the consist configuration information, and the locations along the route. This profile can be used to control movement and/or communication of other vehicle systems, to generate trip plans for other vehicle systems, to diagnose communication faults, and the like.

FIELD

Embodiments of the inventive subject matter described herein relate tocommunications between vehicles in vehicle systems.

BACKGROUND

Some known vehicle consists include several powered vehicles thatgenerate tractive effort for propelling the vehicle consists along aroute. For example, trains may have several locomotives coupled witheach other that propel the train along a track. The locomotives maycommunicate with each other in order to coordinate the tractive effortsand/or braking efforts provided by the locomotives. As one example,locomotives may be provided in a distributed power (DP) arrangement withone locomotive designated as a lead locomotive and other locomotivesdesignated as remote locomotives. The lead locomotive may direct thetractive and braking efforts provided by the remote locomotives during atrip of the consist.

Some known consists use wireless communication between the locomotivesfor coordinating the tractive and/or braking efforts. For example, alead locomotive can issue commands to the remote locomotives. The remotelocomotives receive the commands and implement the tractive effortsand/or braking efforts directed by the commands. In order to ensure thatthe remote locomotives receive the commands, the lead locomotive mayperiodically re-communicate the commands until all of the remotelocomotives confirm receipt of the commands by communicating aconfirmation message to the lead locomotive.

Due to various factors, wireless communication between the locomotivesmay not be possible or may be hindered in certain locations along aroute. While some communication issues may be logged during trips oftrains along some routes, this information is not known to be usedproactively for upcoming trips of other trains.

BRIEF DESCRIPTION

In one embodiment, a method (e.g., for correlating wirelesscommunication performance with vehicle system configurations) includesdetermining wireless message characteristics of wireless messagescommunicated with first vehicles in one or more first vehicle systemsand locations along a route where the wireless message characteristicswere determined. The wireless message characteristics and the locationscan be determined during movement of the one or more first vehiclesystems along a route. The method also can include obtaining consistconfiguration information about the one or more first vehicle systems,and determining a signal propagation profile based on the wirelessmessage characteristics, the locations where the wireless messagecharacteristics were determined, and the consist configurationinformation. The signal propagation profile can represent one or morerelationships between the wireless message characteristics, the consistconfiguration information, and the locations along the route.

In another embodiment, a system (e.g., an analysis system) can includesone or more processors configured to determine wireless messagecharacteristics of wireless messages communicated with first vehicles inone or more first vehicle systems and locations along a route where thewireless message characteristics were determined. The wireless messagecharacteristics and the locations can be determined during movement ofthe one or more first vehicle systems along a route. The one or moreprocessors also can be configured to obtain consist configurationinformation about the one or more first vehicle systems, and todetermine a signal propagation profile based on the wireless messagecharacteristics, the locations where the wireless messagecharacteristics were determined, and the consist configurationinformation. The signal propagation profile can represent one or morerelationships between the wireless message characteristics, the consistconfiguration information, and the locations along the route. The one ormore processors can include a single processor that performs all ofthese operations, two or more processors that each perform all of theseoperations, two or more processors that perform different ones of theabove operations, and/or two or more processors that each perform partof one or more of the above operations.

In another embodiment, a system (e.g., a communication system of avehicle system) includes a control unit configured to be disposedonboard a first vehicle system having plural vehicles for travelingtogether along a route. The control unit can be configured to obtain asignal propagation profile for the route that is representative ofwireless message characteristics for one or more second vehicle systems,consist configuration information of the one or more second vehiclesystems, and locations along the route where the wireless messagecharacteristics were measured during previous travel of the one or moresecond vehicle systems along the route. The control unit can beconfigured to compare consist configuration information of the firstvehicle system with the consist configuration information of the one ormore second vehicle systems in the signal propagation profile todetermine a spatial relationship between the wireless messagecharacteristics of the one or more second vehicle systems and thelocations along the route.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference is now made briefly to the accompanying drawings, in which:

FIG. 1 is a schematic view of one embodiment of a communication systemof a vehicle consist or vehicle system;

FIG. 2 illustrates a flowchart of one embodiment of a method forcorrelating wireless communication performance with vehicle systemconfigurations;

FIG. 3 illustrates one example of a signal propagation map of a routeshown in FIG. 1;

FIG. 4 illustrates another example of a signal propagation map of theroute shown in FIG. 1;

FIG. 5 is a schematic diagram of a propulsion-generating vehicle inaccordance with one embodiment; and

FIG. 6 illustrates a schematic diagram of an analysis system accordingto one embodiment.

DETAILED DESCRIPTION

One or more embodiments of the inventive subject matter described hereinprovide methods and systems for correlating wireless communicationperformance of vehicle systems with configurations of the vehiclesystems along one or more routes. During travel of vehicle systems alongroutes, data related to wireless (e.g., radio-frequency) reception ofmessages communicated to and/or between vehicles in the vehicle systemsis obtained. This data can include characteristics of the signals. Thecharacteristics can include strengths of the received messages (e.g.,receive signal strength), messages that were expected to be received butwere not received (e.g., missing messages), messages that were expectedand that were received as expected (e.g., successfully communicatedmessages), messages that are received but having incomplete or otherwisecorrupted data (e.g., corrupted messages), or the like.

For example, the signal strengths of distributed power (DP) messages orother messages communicated between propulsion-generating vehicles of avehicle system can be measured at different locations along a route.Additionally or alternatively, the failure to receive messagescommunicated at known times (e.g., based on a log or other record ofwhen the messages are transmitted or broadcast) can be determined, thereceipt of messages communicated at known times, and/or messages thatwere received but have missing or otherwise corrupt data in the messagescan be measured or otherwise recorded at different locations along aroute. This data (e.g., wireless message characteristics) can becollected for several different vehicle systems traveling over the sameroute at different times. The wireless message characteristics andlocations at which the vehicles were located when the messages werereceived or should have been received can be communicated to anoff-board location, such as an analysis system disposed off-board thevehicle systems. Additional information, such as consist configurationinformation of the vehicle systems, also may be obtained. Thisinformation can represent the sizes of the vehicle systems (e.g.,lengths of the vehicle systems, the number of vehicles in the vehiclesystems, etc.), the relative positions of certain vehicles in thevehicle systems (e.g., how far propulsion-generating vehicles are fromeach other in the vehicle systems), or other information about how thevehicle systems are configured. Alternatively, the analysis system maybe disposed onboard one or more vehicle systems.

The wireless message characteristics, the locations at which thewireless message characteristics were measured or otherwise determined,and the consist configuration information can be examined to determineone or more signal propagation profiles for a route. The signalpropagation profiles can represent relationships between the wirelessmessage characteristics, the locations along the route, and the consistconfiguration information. For example, for a first consistconfiguration information (e.g., a first length of a vehicle system, afirst distance between two vehicles in the vehicle system, a firstdistribution of the vehicles in the vehicle system, etc.), a firstrelationship of the signal propagation profile can represent thewireless message characteristics that were determined or measured at thecorresponding locations along the route when one or more vehicle systemsformed according to the first consist configuration information traveledalong the route. For different, second consist configuration information(e.g., a longer second length of a vehicle system, a longer seconddistance between two vehicles in the vehicle system, a different, seconddistribution of the vehicles in the vehicle system, etc.), a different,second relationship of the signal propagation profile can represent thewireless message characteristics that were measured or determined at thecorresponding locations along the route when one or more vehicle systemsformed according to the second consist configuration informationtraveled along the route. Several different relationships can be formedfor different consist configurations for a route. Optionally, a signalpropagation profile can represent the wireless message characteristicsthat were measured at different locations along the route for differentpairs of vehicles that were communicating or attempting to communicatewith each other.

The signal propagation profile for a route can be used in a variety ofmanners. For example, the signal propagation profile can be provided toa vehicle system that is to travel on a route so that the vehicle systemcan provide warnings to an onboard operator when the vehicle system isapproaching a segment of the route that is known to have poorcommunications based on the consist configuration information of thevehicle system and the signal propagation profile.

As another example, an energy management system can refer to a signalpropagation profile for a route to determine which segments of the routeare likely to have poor communications. The energy management system cancreate a trip plan for an upcoming trip of the vehicle system over theroute based at least in part on the signal propagation profile. Thistrip plan can dictate operational settings of the vehicle system (e.g.,throttle settings, brake settings, speeds, etc.) as a function of timeand/or distance along the route. The trip plan can be created so thatthe operational settings for one or more of the vehicles do not changeduring travel of the vehicle system through the segments of the routethat are likely to have poor communications (e.g., based on the signalpropagation profile and the consist configuration information of thevehicle system). As a result, the inability for a lead vehicle tocommunicate command signals to one or more remote vehicles in thesesegments of the route may not prevent the vehicle system from being ableto travel according to the trip plan.

Optionally, instead of or in addition to not changing the operationalsettings during travel through segments likely to have poorcommunications, the trip plan could be created and the lead vehicle canlook ahead to determine upcoming locations likely to have poorcommunications. The lead vehicle can communicate scheduled commands tothe remote vehicles before reaching or arriving at these locations. Thescheduled commands can notify the remote vehicles of the operationalsettings designated by the trip plan, as well as the designated timesand/or locations where these operational settings are to be implementedby the remote vehicles. The remote vehicles can receive the scheduledcommands before the designated times and/or before reaching thedesignated locations. Responsive to reaching the designated times and/ordesignated locations, the remote vehicles can implement the designatedoperational settings in the scheduled commands such that, even ifcommunications are interrupted between the remote vehicles and the leadvehicles, the remote vehicles can still operate according to the tripplan.

As another example, prior to forming the vehicle system, the signalpropagation profile may be examined for a route to determine if one ormore different configurations of the vehicle system are likely to resultin better communications during travel over the route than one or moreother configurations.

As another example, during travel over the route, wireless messagecharacteristics may be monitored and compared to the signal propagationprofile. Based on the signal propagation profile and the consistconfiguration information of the vehicle system that is monitoring thewireless message characteristics, the vehicle system may be able todetermine if a fault has occurred with a communication system of thevehicle system. For example, based on the consist configurationinformation of the vehicle system, the signal propagation profile forthe route may indicate an expected wireless message characteristic atone or more locations along the route. If the actual wireless messagecharacteristic of the vehicle system falls below the expected wirelessmessage characteristic, then the actual wireless message characteristicmay indicate a fault with a communication system.

FIG. 1 is a schematic view of one embodiment of a communication system100 of a vehicle consist or vehicle system 102. The illustrated vehiclesystem 102 includes propulsion-generating vehicles 104, 106 (e.g.,vehicles 104, 106A, 106B, 106C, 106D) and non-propulsion-generatingvehicles 108 (e.g., vehicles 108A, 108B, 108C) mechanically coupled witheach other. The communication system 100 can include components(described below) disposed onboard two or more of the vehicles 104, 106.The propulsion-generating vehicles 104, 106 are capable ofself-propulsion while the non-propulsion-generating vehicles 108 are notcapable of self-propulsion. The propulsion-generating vehicles 104, 106are shown as locomotives, the non-propulsion-generating vehicles 108 areshown as rail cars, and the vehicle consist 102 is shown as a train inthe illustrated embodiment. Alternatively, the vehicles 104, 106 mayrepresent other vehicles, such as automobiles, marine vessels, or thelike, and the vehicle consist 102 can represent a grouping or couplingof these other vehicles. In one embodiment, the vehicles 104, 106 maynot be mechanically coupled with each other. For example, the vehicles104, 106 may be separate from each other, but may communicate with eachother to coordinate operations of the vehicles 104, 106. For example,the vehicle 104 may wirelessly communicate operational command signalsto the vehicles 106 that remotely control or direct operational settingsof the vehicles 106 so that the vehicles 104, 106 can remain designateddistances from each other or otherwise travel together. The number andarrangement of the vehicles 104, 106 in the vehicle consist 102 areprovided as one example and are not intended as limitations on allembodiments of the subject matter described herein.

The vehicles 104, 106 can be arranged in a distributed power (DP)arrangement. For example, the vehicles 104, 106 can include a leadvehicle 104 that issues command messages to the other vehicles 106A,106B, 106C, 106D, which are referred to herein as remote vehicles. Thedesignations “lead” and “remote” are not intended to denote spatiallocations of the vehicles 104, 106 in the vehicle consist 102, butinstead are used to indicate which vehicle 104, 106 is communicating(e.g., transmitting, broadcasting, or a combination of transmitting andbroadcasting) operational command messages and which vehicles 104, 106are being remotely controlled using the operational command messages.For example, the lead vehicle 104 may or may not be disposed at thefront end of the vehicle consist 102 (e.g., along a direction of travelof the vehicle consist 102). Additionally, the remote vehicles 106A-Dneed not be separated from the lead vehicle 104. For example, a remotevehicle 106A-D may be directly coupled with the lead vehicle 104 or maybe separated from the lead vehicle 104 by one or more other remotevehicles 106A-D and/or vehicles 108.

The operational command messages may include directives that directoperations of the remote vehicles. These directives can includepropulsion commands that direct propulsion subsystems of the remotevehicles to move at a designated speed and/or power level, brakecommands that direct the remote vehicles to apply brakes at a designatedlevel, and/or other commands. The lead vehicle 104 issues the commandmessages to coordinate the tractive efforts and/or braking effortsprovided by the vehicles 104, 106 in order to propel the vehicle consist102 along a route 110, such as a track, road, waterway, or the like. Theoperational command messages can be communicated using the communicationsystem 100, as described below. In one embodiment, the operationalcommand messages are wirelessly communicated between the vehicles 104,106 using the communication system 100. Optionally, one or more commandsignals may be communicated from an off-board source to one or more ofthe vehicles 104, 106, such as from a tower, dispatch center, off-boardremote control, or the like.

FIG. 2 illustrates a flowchart of one embodiment of a method 200 forcorrelating wireless communication performance with vehicle systemconfigurations. The operations described in connection with the method200 may be performed in an order that differs from that shown in FIG. 2.At 202, consist configuration information of the vehicle system 102 isdetermined. This information can include the size of the vehicle system102, such as the total length of the vehicle system 102, the number ofvehicles 104, 106, 108 (shown in FIG. 1) in the vehicle system 102,distributions or relative positions of the vehicles 104, 106 in thevehicle system 102, separation distances between different pairs of thevehicles 104, 106, or the like. With respect to the distributions orrelative positions of the vehicles 104, 106, this information canrepresent how close or far the different vehicles 104, 106 are from eachother in the vehicle system 102. The consist configuration informationmay be input into a control unit of one or more of the vehicles 104, 106(described below), saved in a memory of one or more of the vehicles 104,106 (described below), or otherwise logged or recorded. At 204, thevehicle system 102 travels along the route 110.

The vehicle system 102 can travel along the route 110 and, during thismovement over the route 110, the vehicles 104, 106 can wirelesslycommunicate with each other. For example, the lead vehicle 104 mayperiodically, occasionally, or otherwise, transmit or broadcastoperational command signals to one or more of the remote vehicles 106.These signals can direct the remote vehicles 106 to change or usevarious operational settings, such as throttle notch positions, brakesettings, or the like. The signals can be communicated to the vehicles106 when the vehicles 106 are at different locations along the route110.

At 206, wireless message characteristics of the messages communicatedbetween the vehicles 104, 106 are monitored. These wireless messagecharacteristics can include received signal strengths. For example, thestrength of the wireless message that are received at one or more of thevehicles 104, 106 can be measured. In one aspect, the received signalstrengths represent magnitudes of electric fields at or near antennasused by the vehicles 104, 106 to receive the signals. The receivedsignal strengths may be expressed in terms of voltage per unit length ofthe electric field, decibels, decibel millivolts per meter, decibelmicrovolts per meter, or in another manner. The received signalstrengths can be measured by communication units of the vehicles 104,106 (described below) that receive the signals.

In one embodiment, the received signal strengths are measured at thelead vehicle 104. For example, the lead vehicle 104 may communicateoperational command signals or messages to the remote vehicles 106 atdifferent times and/or locations during movement along the route 110. Inresponse to broadcasting or transmitting a signal to one or more of theremote vehicles 106, a communication unit of the lead vehicle 104 maymonitor for signals communicated from the remote vehicles 106. Theremote vehicles 106 may send signals in response to the signals from thelead vehicle 104, such as reply signals that confirm receipt of thecommand signals from the lead vehicle 104 and/or provide statuses of theremote vehicles 106 to the lead vehicle 104. The communication unitand/or a control unit (described below) of the lead vehicle 104 mayrecord the location of the lead vehicle 104 and the different signalstrength of reply signals from the different remote vehicles 106.

If no signal is received from one or more of the remote vehicles 106,then the communication unit of the lead vehicle 104 may record areceived signal strength of zero, or “no signal received,” or anotherindication representative of the lead vehicle 104 not receiving aresponse from a remote vehicle 106. This failure to receive a messagewhen the responsive message is expected can be another wireless messagecharacteristic, referred to as a missed message. The lead vehicle 104may expect to receive a message in response to a previous message (e.g.,a response message sent in response to a command message) and, if nomessage is received within a designated time period (e.g., 50milliseconds, 100 milliseconds, one second, or another length of time)and/or from the vehicle 106 to which the command message was sent, thenthe lead vehicle 104 can determine that the location of the lead vehicle104 and/or the remote vehicle 106 resulted in a missed message.

Another example of a wireless message characteristic includes thereceipt of a corrupted message. A corrupted message can include amessage that is only partially received, that includes data that cannotbe understood or interpreted by the vehicle, data that is incorrect(e.g., the data in the message that is received by one vehicle differsin content and/or size from the data in the message that was sent byanother vehicle), or that is otherwise unusable to control operations ofthe vehicles. Another wireless message characteristic can include thesuccessful receipt of a message, such as the receipt of a message withthe data in the message intact and received as expected (e.g., inresponse to a command message).

Additionally or alternatively, the remote vehicles 106 (e.g., controlunits and/or communication units of the remote vehicles 106) can monitorfor signals sent by the lead vehicle 104 and, when a signal is receivedby a remote vehicle 106, the remote vehicle 106 can record (e.g., log)the strength of the received signal and the location of the remotevehicle 106. The remote vehicles 106 optionally can record the failureto receive a message (e.g., a missed message), receipt of a corruptedmessage, and/or successful receipt of a message, along with thelocations of the remote vehicles 106.

At 208, locations of the vehicles 104, 106 are determined. For example,location determining units of the vehicle system 102 and/or the vehicles104, 106 (described below) can identify locations of the vehicles 104,106 as the vehicle system 102 moves along the route 110. The wirelessmessage characteristics and/or locations of the vehicles 104, 106 can berecorded or otherwise saved, such as on one or more memories of thevehicle system 102.

In one embodiment, a control unit and/or location determining unit(described below) of the lead vehicle 104 can determine where the leadvehicle 104 is located at a time that a command signal is sent from thelead vehicle 104 to one or more of the remote vehicles 106. This may berecorded by the control unit and/or location determining unit as thelocation of the lead vehicle 104 that is associated with the wirelessmessage characteristics for one or more reply signals sent from theremote vehicles 106 to the lead vehicle 104 in response to the commandsignal. Alternatively, the location associated with the wireless messagecharacteristics may be determined as the location of the lead vehicle104 after a designated time delay following transmission or broadcast ofthe command signal from the lead vehicle 104. This time delay may bedifferent for different remote vehicles 106. For example, the time delayassociated with a first remote vehicle 106 that is closer to the leadvehicle 104 than a second remote vehicle 106 may be less than the timedelay associated with the second remote vehicle 106. The control unitand/or location determining unit of the lead vehicle 106 may determinethe location of the lead vehicle 104 after this time delay expiresfollowing communication of a command signal to one or more of the remotevehicles 106. If different time delays are used for different remotevehicles 106, then several different locations may be recorded for thelead vehicle 104 for the wireless message characteristics associatedwith the reply messages or reply signals sent by the remote vehicles 106to the lead vehicle 106 in response a command message or command signalfrom the lead vehicle 106. Optionally, the control units and/or locationdetermining units onboard the remote vehicles 106 can record locationsof the remote vehicles 106 at times when the wireless messagecharacteristics are measured or determined, and/or when the signals arereceived (for which the wireless message characteristics are measured orotherwise determined).

At 210, a determination is made as to whether the trip of the vehiclesystem 102 along the route 110 is complete. For example, a determinationmay be made as to whether the vehicle system 102 is no longer movingalong the route 110, whether the vehicle system 102 is no longer mannedby one or more operators, whether a designated time period has expired(even if the vehicle system 102 continues to move along the route 110),or the like. If the trip is not complete, then flow of the method 200can return to 204 so that the vehicle system 102 continues to travelalong the route 110 while wireless message characteristics and locationsof the vehicles 104, 106 are monitored. If the trip is complete, thenflow of the method 200 can proceed to 212. At 212, the monitoring of thewireless message characteristics and/or locations of the vehicles 104,106 can be completed.

The wireless message characteristics, locations 300 of the vehicles 104,106, and the consist configuration information can be used to generate asignal propagation profile for the route 110. The wireless messagecharacteristics, vehicle locations 300, and the consist configurationinformation can be obtained from several different trips of the same ordifferent vehicle systems 102 over the same route 110. The wirelessmessage characteristics, vehicle locations 300, and the consistconfiguration information can be provided to an analysis system(described below) to determine the signal propagation profile for theroute 110.

The wireless message characteristics that previously were measured forone or more vehicle systems 102 traveling over the route 110 can beobtained from the vehicle systems 102 for examination by an analysissystem (described below). Additionally, the locations at which thesewireless message characteristics were measured can be obtained, as wellas the consist configuration information of the vehicle systems 102.Several different vehicle systems 102 having different or the sameconsist configuration information can communicate the wireless messagecharacteristics and locations to a memory of the analysis systemdescribed below. This data can be collected and/or updated over anextended period of time, such as several days, weeks, months, years, orthe like.

As described above, the lead and/or remote vehicles 104, 106 can log orotherwise record the wireless message characteristics and associatedlocations of the vehicles 104, 106 during trips of the vehicle systems102 along the route 110. This information can be communicated to theanalysis system, such as after the trips are completed, during travelalong the route 110, or at another time. In one aspect, other data maybe communicated to the analysis system, such as time-varying conditions(e.g., environmental conditions that change with respect to time, suchas weather conditions, precipitation, wind, or the like).

The wireless message characteristics, associated locations, and theconsist configuration information can be examined to correlate thewireless message characteristics and locations with different consistconfiguration information. In one aspect, other data may be correlatedwith the message characteristics and/or locations, such as weatherconditions. The wireless message characteristics that are determined forvehicle systems 102 having the same or similar consist configurationinformation may be used to form different parts of a signal propagationprofile for the route 110. For example, the wireless messagecharacteristics that are determined for a first group of the vehiclesystems 102 traveling over the same route 110 and having the same orsimilar consist configuration information can be used to determine atleast part of a signal propagation profile for the route 110.Additionally, the wireless message characteristics that are determinedfor a different, second group of vehicle systems 102 traveling over thesame route 110 but having different consist configuration informationthan the first group may be used to form another part of the signalpropagation profile for the route 110. In one aspect, different signalpropagation profiles can be determined for different time-varyingconditions, such as different weather conditions. For example, a firstsignal propagation profile may represent the wireless messagecharacteristics and vehicle locations for a group of vehicles havingfirst consist configuration information and during first weatherconditions (e.g., clear skies). A different, second signal propagationprofile may represent the wireless message characteristics and vehiclelocations for the same or different group of vehicles having the same ordifferent consist configuration information and during different, secondweather conditions (e.g., rain).

In one aspect, the signal propagation profile for the route 110 includesone or more signal propagation maps of the route 110. These maps canrepresent locations and associated wireless message characteristics atthose locations for vehicle systems 102 having various consistconfigurations.

FIG. 3 illustrates one example of a signal propagation map 302 of theroute 110 shown in FIG. 1. The signal propagation map 302 represents aportion of a signal propagation profile of the route 110 that showsseveral locations 300 where wireless message characteristics weredetermined. The locations 300 can represent the wireless messagecharacteristics determined during previous trips of one or more vehiclesystems 102 having the same or similar consist configuration informationover the same route 110. The locations 300 may be shown on an outputdevice (described below) onboard one or more of the vehicles 104, 106 asicons or other objects that represent the wireless messagecharacteristics. Optionally, the map 302 may include the locations 300and the signal strengths recorded or represented in another manner, suchas a list, table, spreadsheet, graphical curve, or the like, thatassociates different locations 300 with the signal strengths measured byone or more vehicle systems 102 at those locations. In one embodiment,if multiple vehicle systems 102 measure different wireless messagecharacteristics at or near the same location 300 (e.g., at locationsthat are within ten meters, twenty meters, or the like, of each other),then these signal strengths may be combined by calculating an average,median, or the like.

FIG. 4 illustrates another example of a signal propagation map 402 ofthe route 110 shown in FIG. 1. The signal propagation map 402 representsanother portion of the signal propagation profile of the route 110 thatincludes the signal propagation map 302 shown in FIG. 3. The map 402also includes several locations 400 (e.g., locations 400A, 400B) wherewireless message characteristics were measured.

The maps 302, 402 may differ from each other in that the map 302 may begenerated based on the wireless message characteristics measured for oneor more vehicle systems 102 having the same or similar first consistconfiguration information while the map 402 is based on the wirelessmessage characteristics measured for one or more other vehicle systems102 having the same or similar second consist configuration informationthat is different from the first consist configuration information. Theconsist configuration information for two or more vehicle systems 102may be similar when the consist configuration information for thevehicle systems 102 is within a designated range of each other. Forexample, if the lengths of the vehicle systems 102, the number ofvehicles 104, 106, 108 in the vehicle systems 102, or the like, arewithin 5%, 10%, 20%, or the like, of each other, then the wirelessmessage characteristics measured for these vehicle systems 102 may beincluded together to form a common part of the signal propagationprofile, such as being used to create the map 302 or 402. In theillustrated example, the map 302 may be created using the wirelessmessage characteristics measured for one or more vehicle systems 102having ninety vehicles 104, 106, 108 while the map 402 is created usingthe wireless message characteristics measured for one or more vehiclesystems 102 having one hundred and thirty vehicles 104, 106, 108.

The signal propagation profile for the route 110 can represent thewireless message characteristics at different locations 300, 400 alongthe route 110 for the vehicle systems 102 having different consistconfiguration information. In the illustrated example, the wirelessmessage characteristics at the locations 300 in the map 302 of thesignal propagation profile are sufficiently strong (e.g., the wirelessmessage characteristics exceed a designated threshold, such as at least−30 dBm, at least −40 dBm, or the like) to indicate that the signalswere received by the vehicles 104 and/or 106 at the associated locations300. Similarly, the wireless message characteristics at the locations400A in the map 402 of the signal propagation profile are sufficientlystrong to indicate that the signals were received. In contrast, thewireless message characteristics at the locations 400B in the map 402may not be sufficiently strong (e.g., the wireless messagecharacteristics do not exceed the designated threshold) to indicate thatthe signals were received by the vehicles 104 and/or 106 at theassociated locations 400B. Additional maps, lists, databases, or othermemory structures representative of the wireless message characteristicsmeasured or determined at different locations along the route 110 forvehicle systems 102 having different consist configuration informationcan be determined and used to form the signal propagation profile forthe route 110.

The signal propagation profiles for the route 110 represent spatialrelationships between the wireless message characteristics measured ordetermined during one or more previous trips of one or more vehiclesystems along the same route 110. The spatial relationships may berepresented as maps, tables, lists, or the like, that correlate orotherwise match the previously measured or determined wireless messagecharacteristics with the locations at or near where the vehicles 104,106 were located when the characteristics were measured or determined.The signal propagation profiles also can depend or change based on theconsist configuration information of the vehicle systems. As a result,the signal propagation profile for the route 110 represents one or morerelationships between the wireless message characteristics, thelocations at which the vehicles 104 and/or 106 were located when thewireless message characteristics were measured or determined, and theconsist configuration information. The signal propagation profiles canbe used to assist in the upcoming travel of one or more other vehiclesystems 102 along the route 110, to plan for upcoming trips of thesevehicle systems 102 along the route 110, or the like.

For example, in addition or in place of the maps 300, 400, informationsuch as in the table below may be the signal propagation profiles fortwo different consist configurations (e.g., “Consist Configuration A”and “Consist Configuration B”):

Consist Configuration A Consist Configuration B Location RSS Rx QLocation RSS Rx Q 1 −60 1 1 2 −70 1 1 3 −65 1 1 3 −77 1 1 4 −80 1 1 4−90 1 0 6 −70 1 1 5 −105 1 1 8 0 0 0 8 0 0 0 13 −115 1 1 9 0 0 0 14 −901 1 13 −110 1 1 16 −60 1 1 15 −70 1 1 22 −60 1 1 17 −65 1 1 24 −60 1 120 −70 1 1

While only two signal propagation profiles are shown in the table,optionally, a single signal propagation profile or more than two signalpropagation profiles may be used. In the above table, the wirelessmessage characteristics measured or determined for the different consistconfigurations are listed, as well as the locations where the wirelessmessage characteristics are measured or determined. The “Locations”represent different distances or locations along the route 110 (e.g.,expressed in terms of miles, kilometers, or the like), the “RSS”represent received signal strengths (e.g., in decibels) of wirelessmessages received at or near (e.g., within a designated distance, suchas 10 meters, 100 meters, or the like) the corresponding location, the“Rx” indicate whether the wireless message(s) were received at or nearthe corresponding location (e.g., with 1 indicating successful receiptof the message and 0 indicating that no message was received at thelocation, even though a message was sent and expected to be received atthat location), and the “Q” indicate whether the received message wascorrupted (e.g., with 1 indicating that the data in the message was notcorrupted and 0 indicating that the data was corrupted or that nomessage was received).

The consist configurations in the signal propagation profile canrepresent different sizes of vehicle systems 102. Additionally oralternatively, the consist configurations can represent differentdistances between pairs of a lead vehicle and a remote vehicle. In sucha situation, a single vehicle system 102 may have several consistconfigurations, with two or more of the signal propagation profilesassociated with different pairs of the lead vehicle and different remotevehicles. The signal propagation profiles can be examined to identifypotential segments of the route 110 where a vehicle system 102 havingthe same consist configuration may experience problems with wirelesscommunications.

As one example, the signal propagation profile for a route can be usedby one or more control units (described below) of the vehicle system 102to identify upcoming locations along the route where communicationproblems are expected to occur. During movement of the vehicle system102 along the route 110, the control unit of the lead vehicle 104 candetermine a current location of the vehicle system 102 (e.g., based ondata generated or obtained by the location determining unit describedbelow) and examine the signal propagation profile to determine if one ormore upcoming locations along the route 110 are likely to have poorcommunications. With respect to the signal propagation profilerepresented in the table shown above, a vehicle system 102 that isapproaching the seventy mile or kilometer location along the route 110can examine the signal propagation profile.

If the vehicle consist 102 has consist configuration information that isthe same or similar to the Consist Configuration A, then the controlunit of the vehicle consist 102 can examine the wireless messagecharacteristics at the locations associated with the eighth and/orthirteenth mile or kilometer locations in the signal propagationprofile. As shown above, the wireless message characteristics in thesignal propagation profile shown above for the Consist Configuration Aindicate that wireless messages may not be received at or near theeighth mile or kilometer location along the route 110 and/or thatwireless messages may have low strengths at or near the thirteenth mileor kilometer along the route 110. With respect to received signalstrengths, the control unit can compare the received signal strengths toone or more thresholds (e.g., −80 dBm, −100 dBm, −115 dBm, or the like)and determine whether the received signal strengths are lower or greaterthan the threshold. If the received signal strengths indicate weakerreceived signal strengths than the threshold, then the control unit maydetermine that communication problems are expected at or near thecorresponding locations.

On the other hand, if the vehicle system 102 has consist configurationinformation that is the same or similar to the Consist Configuration B,then the control unit can determine that the received signal strengthsat or near the fifth and thirteenth mile or kilometers distancesindicate potential communication problems with weak messages, that themissed messages at or near the eighth and ninth mile or kilometerdistances indicate that messages may be missed at or near thoselocations, and/or that the messages may be corrupted at or near thefourth mile or kilometer distance.

The control unit can then use one or more output devices (describedbelow) onboard the vehicle system 102 to warn the operator of theupcoming locations and the potential inability for the vehicles 104, 106or for a group of the vehicles 104, 106 to communicate in theselocations. The operator may then adjust how the vehicle system 102 iscontrolled through these locations. For example, the control unit maydirect the operator to not remotely change throttle positions of theremote vehicles 106 or otherwise control the vehicle system 102 in sucha manner that would involve wireless communication between the vehicles104, 106 in these locations.

As another example, an energy management system (described below) canrefer to the signal propagation profile to create a trip plan for thevehicle system 102 to travel over all or at least a portion of the route110 in an upcoming or current trip. The trip plan dictates or designatesoperational settings of the vehicle system 102 as a function of distanceand/or time along the route 110. For example, the trip plan canrepresent different throttle settings or notch positions, brakesettings, speeds, or the like, of the vehicle system 102 and/or forindividual vehicles 104, 106 at different locations along the route 110and/or different times during movement along the route 110. The tripplan may be created to dictate the operational settings of the vehiclesystem 102 for portions of the route 110 before the vehicle system 102travels over those portions of the route 110.

The energy management system can generate the trip plan by examining thesignal propagation profile. For example, the energy management systemcan determine the consist configuration information of the vehiclesystem 102 for which the trip plan is being generated and examine thesignal propagation profile to determine if any segments of the route 110are associated with locations having wireless message characteristicsthat indicate potential communication problems. The trip plan can thenbe created so that the operational settings do not change during travelof the vehicle system 102 in these segments. Optionally, scheduledcommands may be communicated to the remote vehicles based on the tripplan and the segments so that the remote vehicles are aware of theoperational settings designated by the trip plan in these segmentsbefore reaching the segments and/or reaching designated times of thetrip plan, as described above. In the signal propagation profiles shownin the table above, the energy management system may create a trip planfor a vehicle system 102 having the same or similar consistconfiguration information as the Consist Configuration A so that thevehicle system 102 does not change operational settings (e.g., throttlenotch positions, brake settings, speeds, or the like) during travelthrough the eighth and/or thirteenth mile or kilometer location. Withrespect to the Consist Configuration B, the energy management system cancreate the trip plan so that operational settings are not changed duringtravel through the fourth, fifth, eighth, ninth, and/or thirteenth mileor kilometer locations along the route 110.

Optionally, if the consist configuration information in the signalpropagation profiles represent different distances between pairs of leadand remote vehicles, then the trip plan can be formed so that theoperational settings of the remote vehicles represented by the consistconfiguration information of the signal propagation profile do notchange at or near the locations associated with low received signalstrengths, missed messages, and/or corrupted messages.

As another example, prior to forming the vehicle system, the signalpropagation profile may be examined for a route to determine if one ormore different configurations of the vehicle system 102 are likely toresult in better communications during travel over the route than one ormore other configurations. For example, in a vehicle yard (e.g., a railyard) where different vehicles 104, 106, 108 are considered for beingcombined into a vehicle system 102, an analysis system (described below)can examine the signal propagation profile for the route 110 todetermine which vehicles 104, 106, 108 should be included in the vehiclesystem 102. In the signal propagation profile shown above, vehiclesystems having the consist configuration information that matches theConsist Configuration B appear to have poorer communications in morefrequent locations along the route 110 when compared to the ConsistConfiguration A. Therefore, the analysis system may recommend formingthe vehicle system 102 according to the same consist configurationinformation as is represented by the Consist Configuration A. Thisrecommendation may be presented to one or more personnel responsible forforming the vehicle system 102 using one or more output devices(described below) of the analysis system.

The signal propagation profile optionally may be used to determine ifone or more communication units of the vehicle system 102 are notworking or may be otherwise degraded. During travel over the route 110,wireless message characteristics may be monitored at various locationsalong the route 110 by the communication units of the moving vehiclesystem 102. These monitored signal strengths can be compared to thewireless message characteristics in the signal propagation profiles atthe same or nearby locations (e.g., within a designated distance of tenmeters, twenty meters or the like) for the same or similar consistconfiguration information as the vehicle system 102 that is currentlytraveling along the route 110. If the currently monitored signalstrengths are lower than the wireless message characteristics in thesignal propagation profile at the same or similar location, then one ormore communication units and/or control units of the vehicle system 102may determine that one or more of the communication units are notworking properly. For example, if no signal is received in or near alocation where the signal propagation profile indicates that arelatively strong signal should be received (e.g., the signalpropagation profile includes a wireless message characteristic greaterthan the designated threshold at or near that location), then a faultwith one or more communication units may be identified. As anotherexample, if the wireless message characteristic is significantly less(e.g., by at least a designated threshold, such as −20 dB, −10 dB, oranother value) than the wireless message characteristic in the signalpropagation profile at or near the same location, then a fault with oneor more communication units may be identified. In response toidentifying such a fault, the control unit and/or communication unit ofone or more of the vehicles 104, 106 may generate a warning that isconveyed to the operator of the vehicle system 102 via one or more ofthe output devices.

FIG. 5 is a schematic diagram of a propulsion-generating vehicle 500 inaccordance with one embodiment. The vehicle 500 may represent one ormore of the vehicles 104, 106 shown in FIG. 1. The vehicle 500 includesa communication system 502 that includes a control unit 504 thatcontrols operations of the vehicle 500. The control unit 504 can includeor represent one or more hardware circuits or circuitry that include,are connected with, or that both include and are connected with one ormore processors, controllers, or other hardware logic-based devices. Asdescribed above, the control unit 504 can perform a variety ofoperations of the vehicle 500, such as automatically controllingoperations of the vehicle 500 based on the operational settingsdesignated by a trip plan, determining when the vehicle system 102 isapproaching a segment of the route 110 that is associated with lowwireless message characteristics based on the consist configurationinformation of the vehicle system 102, generating a warning signal towarn the operator of the vehicle 500 or vehicle system 102 in responsethereto, and the like.

The control unit 504 is connected with an input device 506 and an outputdevice 508. The control unit 506 can receive manual input from anoperator of the vehicle 500 through the input device 506. The inputdevice 506 represents one or more touchscreens, keyboards, microphones,styluses, or the like. The control unit 504 can present information tothe operator using the output device 508, which can represent a displayscreen (e.g., touchscreen or other screen), speakers, printer, or thelike. This output can include a warning of an upcoming segment of theroute 110 where communication problems are expected or predicted tooccur based on the signal propagation profile of the route 110, theconsist configuration information of the vehicle system 102 thatincludes the control unit 504, and the upcoming locations of the route110. The output optionally may include a display of measured signalstrengths that are being measured by the vehicle 500, displays ofoperational settings designated by a trip plan (so that the operator canmanually control the vehicle 500 based on the operational settings),display of one or more portions of the signal propagation profile of theroute 110 (e.g., maps, tables, lists, or the like, of the wirelessmessage characteristics and associated locations, etc.), or otherinformation.

The control unit 504 is operably connected with a propulsion subsystem510 of the powered vehicle 500, such as by being connected with thepropulsion system 510 by one or more wired and/or wireless connections.The propulsion subsystem 510 provides tractive effort and/or brakingeffort of the vehicle 500. The propulsion subsystem 510 may include orrepresent one or more engines, motors, alternators, generators, brakes,batteries, turbines, and the like, that operate to propel the vehicle500 under the manual or autonomous control that is implemented by thecontrol unit 504. For example, the control unit 504 can generate controlsignals autonomously or based on manual input and/or operationalsettings designated by a trip plan that are used to direct operations ofthe propulsion subsystem 510.

The control unit 504 also is operably connected with a communicationunit 512 and a memory 514 described herein. The memory 514 can representan onboard device that electronically and/or magnetically stores data.For example, the memory 514 may represent a computer hard drive, randomaccess memory, read-only memory, dynamic random access memory, anoptical drive, or the like. The memory 514 may store, log, or otherwiserecord the wireless message characteristics that are measured orotherwise obtained by the communication unit 512 during movement of thevehicle 500. These wireless message characteristics may be communicatedto the analysis system described below for use in creating and/orupdating a signal propagation profile for the route 110. The memory 514optionally may store part or all of the signal propagation profile forthe route 110, so that the control unit 504 and/or energy managementsystem (described below) of the vehicle 500 can refer to the signalpropagation profile during travel of the vehicle 500, as describedabove.

The communication unit 512 includes or represents hardware and/orsoftware that is used to communicate with other vehicles 500 in thevehicle system 102, such as one or more other vehicles 104, 106. Forexample, the communication unit 512 may include a transceiver or antenna516 and associated circuitry for wirelessly communicating (e.g.,communicating and/or receiving) signals. The communication unit 512optionally may communicate with the analysis system described below,such as to send wireless message characteristics measured by thecommunication unit 512, to receive a signal propagation profile for theroute 110, or the like. The communication unit 512 can measure thestrengths of the signals received by the vehicle 500, as describedabove.

The location determining unit 518 of the vehicle 500 includes hardwareand/or software that identifies locations of the vehicle 500 and/orvehicle system 102 as the vehicle 500 moves along the route 110, asdescribed above. In one embodiment, the location determining unit 518includes a global positioning system receiver that generates datarepresentative of locations of the vehicle 500. This data may becommunicated or otherwise accessible to the control unit 504 and/or thecommunication unit 512, so that the locations of the vehicle 500 can bemonitored to associate locations with wireless message characteristicsmeasured by the communication unit 512, to identify potentialcommunication problems for upcoming segments of the route 110, or thelike. Optionally, the location determining unit 518 can include one ormore processors, controllers, or the like, that calculate the locationsof the vehicle 500 based on other data, such as speeds at which wheelsof the vehicle 500 rotate, airspeed of ambient air outside of thevehicle 500, elapsed time and speed of the vehicle 500 since a knownlocation, or the like.

The energy management system 520 of the vehicle 500 represents hardwareand/or software, such as one or more processors, controllers, or thelike, that create and/or modify trip plans for the vehicle 500 and/orvehicle system 102. The energy management system 520 can create the tripplans so as to avoid requiring the communication of wireless commandsignals to one or more other vehicles 106 from the vehicle 500 inlocations that are likely to have communication problems based on thesignal propagation profile of the route 110, as described above. Theenergy management system 520 alternatively may be disposed off-board thevehicle 500.

FIG. 6 illustrates a schematic diagram of an analysis system 600according to one embodiment. As described above, the analysis system 600examines wireless message characteristics measured by one or morevehicle systems 102 during travel along the route 110, locations of thevehicles 104, 106 associated with the wireless message characteristics,and consist configuration information of the vehicle systems 102. Basedon this information, the analysis system 600 can determine a signalpropagation profile for the route 110. For example, the analysis system600 can separate the wireless message characteristics and associatedlocations from multiple different vehicle systems 102 into differentgroups based on the consist configuration information of the vehiclesystems 102. The analysis system 600 can then match the locations andthe associated wireless message characteristics with each other withinthe different groups to generate the signal propagation profile.

The analysis system 600 is shown as being disposed off-board the vehiclesystem 102. Alternatively, some or all of the analysis system 600 isdisposed onboard the vehicle system 102. The analysis system 600includes a communication unit 602 that communicates with vehicle systems102 via one or more wired and/or wireless connections. The communicationunit 602 may include a transceiver and/or antenna 604, and associatedcircuitry, for communicating with the vehicle systems 102 to receivemeasured signal strengths, locations, consist configuration information,and the like. The communication unit 602 may communicate signalpropagation profiles to the vehicle systems 102, recommendations for howto build vehicle systems 102 to personnel at vehicle yards that areforming the vehicle systems 102 based on the signal propagationprofiles, or the like.

The analysis system 600 includes one or more processors 606 that examinethe wireless message characteristics, associated locations, and consistconfiguration information from different vehicle systems 102 to form thesignal propagation profiles for one or more routes 110, as describedherein. The processors 606 optionally may generate recommendations forhow to form vehicle systems 102 so that the vehicle systems 102 have theconsist configuration information for the route 110 to reduce oreliminate the likelihood of communication problems based on the signalpropagation profile for the route 110.

A memory 608 of the analysis system 600 may be similar or identical tothe memory 514 of the vehicle 500 shown in FIG. 5. The memory 608 canstore the wireless message characteristics, associated locations,consist configuration information, signal propagation profiles, and thelike, described above. The analysis system 600 also includes an inputdevice 610 and an output device 612. The input device 610 represents oneor more touchscreens, keyboards, microphones, styluses, or the like. Theinput device 610 can be used by an operator to input information such asconsist configuration information, wireless message characteristics,locations, or the like, into the memory 608. The output device 612 canrepresent a display screen (e.g., touchscreen or other screen),speakers, printer, or the like, that generates output for one or moreoperators. This output can include signal propagation profiles,recommendations for forming vehicle systems 102, or the like.

In one embodiment, a method (e.g., for correlating wirelesscommunication performance with vehicle system configurations) includesdetermining wireless message characteristics of wireless messagescommunicated with first vehicles in one or more first vehicle systemsand locations along a route where the wireless message characteristicswere determined. The wireless message characteristics and the locationscan be determined during movement of the one or more first vehiclesystems along a route. The method also can include obtaining consistconfiguration information about the one or more first vehicle systems,and determining a signal propagation profile based on the wirelessmessage characteristics, the locations where the wireless messagecharacteristics were determined, and the consist configurationinformation. The signal propagation profile can represent one or morerelationships between the wireless message characteristics, the consistconfiguration information, and the locations along the route.

In one aspect, the wireless message characteristics can include one ormore of received signal strengths of the wireless messages, receipt ofmessages communicated at known times, missed wireless messages of thewireless messages, or corrupted wireless messages of the wirelessmessages.

In one aspect, the wireless messages can include distributed powermessages wirelessly communicated between the first vehicles in the oneor more first vehicle systems during remote control of one or moreremote vehicles of the first vehicles by one or more lead vehicles ofthe first vehicles.

In one aspect, the consist configuration information can include one ormore of a size of the one or more vehicle systems or relative positionsof the vehicles in the one or more first vehicle systems during themovement of the one or more first vehicle systems along the route.

In one aspect, the signal propagation profile can include a spatialrelationship between the wireless message characteristics of thewireless messages and the locations along the route.

In one aspect, the method also can include creating a trip plan for anupcoming trip of a second vehicle system based on the signal propagationprofile. The trip plan can designate operational settings of the secondvehicle system at one or more different times or distances along theroute and that are to be wirelessly communicated from a lead vehicle ofthe second vehicle system to one or more remote vehicles of the secondvehicle system for wireless control of the one or more remote vehiclesaccording to the trip plan. The trip plan can be created based on thesignal propagation profile such that the operational settings that aredesignated in the trip plan for the one or more remote vehicles do notchange during movement of the second vehicle system through one or moresegments of the route based on the signal propagation profile.

In one aspect, the method also can include creating a trip plan for anupcoming trip of a second vehicle system based on the signal propagationprofile. The trip plan can designate operational settings of the secondvehicle system at one or more different times or distances along theroute and that are to be wirelessly communicated from a lead vehicle ofthe second vehicle system to one or more remote vehicles of the secondvehicle system for wireless control of the one or more remote vehiclesaccording to the trip plan. The method also can include identifying oneor more upcoming segments of the route associated with an inability towirelessly communicate between the lead vehicle and the one or moreremote vehicles based on the wireless message characteristics associatedwith the one or more upcoming segments of the route, and wirelesslycommunicating scheduled commands from the lead vehicle to the one ormore remote vehicles prior to the one or more remote vehicles reachingthe one or more upcoming segments. The scheduled commands can includethe operational settings designated by the trip plan for one or morelocations within the one or more upcoming segments of the route.

In one aspect, the method also can include identifying one or moresecond vehicles to be included in a second vehicle system for travelalong the route during an upcoming trip of the second vehicle systembased on the signal propagation profile.

In one aspect, the method also can include generating one or morewarnings to an operator of a second vehicle system moving along theroute of one or more upcoming segments of the route where wirelesscommunications between a lead vehicle and one or more remote vehicles ofthe second vehicle system are degraded based on the signal propagationprofile.

In one aspect, the method also can include monitoring additionalwireless message characteristics of additional wireless messagescommunicated between a lead vehicle and one or more remote vehicles in asecond vehicle system during movement of the second vehicle system alongthe route, and generating a warning indicative of a fault in acommunication system of the second vehicle system based on a comparisonbetween the additional wireless message characteristics for the secondvehicle system and the signal propagation profile.

In another embodiment, a system (e.g., an analysis system) can includesone or more processors configured to determine wireless messagecharacteristics of wireless messages communicated with first vehicles inone or more first vehicle systems and locations along a route where thewireless message characteristics were determined. The wireless messagecharacteristics and the locations can be determined during movement ofthe one or more first vehicle systems along a route. The one or moreprocessors also can be configured to obtain consist configurationinformation about the one or more first vehicle systems, and todetermine a signal propagation profile based on the wireless messagecharacteristics, the locations where the wireless messagecharacteristics were determined, and the consist configurationinformation. The signal propagation profile can represent one or morerelationships between the wireless message characteristics, the consistconfiguration information, and the locations along the route. The one ormore processors can include a single processor that performs all ofthese operations, two or more processors that each perform all of theseoperations, two or more processors that perform different ones of theabove operations, and/or two or more processors that each perform partof one or more of the above operations.

In one aspect, the wireless message characteristics can include one ormore of received signal strengths of the wireless messages, receipt ofmessages communicated at known times, missed wireless messages of thewireless messages, or corrupted wireless messages of the wirelessmessages.

In one aspect, the wireless messages can include distributed powermessages that were wirelessly communicated between the first vehicles inthe one or more first vehicle systems during remote control of one ormore remote vehicles of the first vehicles by one or more lead vehiclesof the first vehicles.

In one aspect, the consist configuration information can include one ormore of a size of the one or more vehicle systems or relative positionsof the vehicles in the one or more first vehicle systems during themovement of the one or more first vehicle systems along the route.

In one aspect, the one or more processors can be configured to identifyone or more second vehicles to be included in a second vehicle systemfor travel along the route during an upcoming trip of the second vehiclesystem based on the signal propagation profile.

In another embodiment, a system (e.g., a communication system of avehicle system) includes a control unit configured to be disposedonboard a first vehicle system having plural vehicles for travelingtogether along a route. The control unit can be configured to obtain asignal propagation profile for the route that is representative ofwireless message characteristics for one or more second vehicle systems,consist configuration information of the one or more second vehiclesystems, and locations along the route where the wireless messagecharacteristics were measured during previous travel of the one or moresecond vehicle systems along the route. The control unit can beconfigured to compare consist configuration information of the firstvehicle system with the consist configuration information of the one ormore second vehicle systems in the signal propagation profile todetermine a spatial relationship between the wireless messagecharacteristics of the one or more second vehicle systems and thelocations along the route.

In one aspect, the consist configuration information of the firstvehicle system can include one or more of a size of the first vehiclesystem or relative positions of the vehicles in the first vehiclesystem.

In one aspect, the system also can include an energy management systemconfigured to create a trip plan for a trip of the first vehicle systemalong the route based on the signal propagation profile. The trip plancan designate operational settings of the first vehicle system at one ormore different times or distances along the route and that are to bewirelessly communicated between the vehicles of the first vehicle systemfor wireless control of one or more of the vehicles according to thetrip plan.

In one aspect, the energy management system can be configured to createthe trip plan based on the signal propagation profile such that theoperational settings that are designated in the trip plan for the one ormore vehicles in the first vehicle system do not change during movementof the first vehicle system through one or more segments of the routebased on the spatial relationship between the wireless messagecharacteristics of the one or more second vehicle systems and thelocations along the route.

In one aspect, the control unit can be configured to identify one ormore upcoming segments of the route associated with an inability towirelessly communicate with one or more of the vehicles in the firstvehicle system based on the wireless message characteristics associatedwith the one or more upcoming segments of the route from the spatialrelationship between the wireless message characteristics of the one ormore second vehicle systems and the locations along the route. Thecontrol unit also can be configured to communicate scheduled commands tothe one or more vehicles prior to the one or more vehicles reaching theone or more upcoming segments, the scheduled commands including theoperational settings designated by the trip plan for one or morelocations within the one or more upcoming segments of the route.

In one aspect, the control unit can be configured to generate one ormore warnings to an operator of the first vehicle system moving alongthe route of one or more upcoming segments of the route where wirelesscommunications between the vehicles of the first vehicle system arepredicted to be degraded based on the spatial relationship between thewireless message characteristics of the one or more second vehiclesystems and the locations along the route.

In one aspect, the control unit can be configured to monitor additionalwireless message characteristics of additional wireless communicationsbetween the vehicles during movement of the first vehicle system alongthe route and to generate a warning indicative of a fault in acommunication system of the first vehicle system based on a comparisonbetween the additional wireless message characteristics for the firstvehicle system and the spatial relationship between the wireless messagecharacteristics of the one or more second vehicle systems and thelocations along the route.

It is to be understood that the above description is intended to beillustrative, and not restrictive. For example, the above-describedembodiments (and/or aspects thereof) may be used in combination witheach other. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the inventivesubject matter without departing from its scope. While the dimensionsand types of materials described herein are intended to define theparameters of the inventive subject matter, they are by no meanslimiting and are exemplary embodiments. Many other embodiments will beapparent to one of ordinary skill in the art upon reviewing the abovedescription. The scope of the inventive subject matter should,therefore, be determined with reference to the appended clauses, alongwith the full scope of equivalents to which such clauses are entitled.In the appended clauses, the terms “including” and “in which” are usedas the plain-English equivalents of the respective terms “comprising”and “wherein.” Moreover, in the following clauses, the terms “first,”“second,” and “third,” etc. are used merely as labels, and are notintended to impose numerical requirements on their objects. Further, thelimitations of the following clauses are not written inmeans-plus-function format and are not intended to be interpreted basedon 35 U.S.C. §112(f), unless and until such clause limitations expresslyuse the phrase “means for” followed by a statement of function void offurther structure.

This written description uses examples to disclose several embodimentsof the inventive subject matter and also to enable one of ordinary skillin the art to practice the embodiments of inventive subject matter,including making and using any devices or systems and performing anyincorporated methods. The patentable scope of the inventive subjectmatter is defined by the clauses, and may include other examples thatoccur to one of ordinary skill in the art. Such other examples areintended to be within the scope of the clauses if they have structuralelements that do not differ from the literal language of the clauses, orif they include equivalent structural elements with insubstantialdifferences from the literal languages of the clauses.

The foregoing description of certain embodiments of the presentinventive subject matter will be better understood when read inconjunction with the appended drawings. To the extent that the figuresillustrate diagrams of the functional blocks of various embodiments, thefunctional blocks are not necessarily indicative of the division betweenhardware circuitry. Thus, for example, one or more of the functionalblocks (for example, processors or memories) may be implemented in asingle piece of hardware (for example, a general purpose signalprocessor, microcontroller, random access memory, hard disk, and thelike). Similarly, the programs may be standalone programs, may beincorporated as subroutines in an operating system, may be functions inan installed software package, and the like. The various embodiments arenot limited to the arrangements and instrumentality shown in thedrawings.

As used herein, an element or step recited in the singular and proceededwith the word “a” or “an” should be understood as not excluding pluralof said elements or steps, unless such exclusion is explicitly stated.Furthermore, references to “one embodiment” of the present inventivesubject matter are not intended to be interpreted as excluding theexistence of additional embodiments that also incorporate the recitedfeatures. Moreover, unless explicitly stated to the contrary,embodiments “comprising,” “including,” or “having” an element or aplurality of elements having a particular property may includeadditional such elements not having that property.

What is claimed is:
 1. A method comprising: determining wireless messagecharacteristics of wireless messages communicated with first vehicles inone or more first vehicle systems and locations along a route where thewireless message characteristics were determined, the wireless messagecharacteristics and the locations determined during movement of the oneor more first vehicle systems along the route; obtaining consistconfiguration information about the one or more first vehicle systems;and determining a signal propagation profile based on the wirelessmessage characteristics, the locations where the wireless messagecharacteristics were determined, and the consist configurationinformation, the signal propagation profile representative of one ormore relationships between the wireless message characteristics, theconsist configuration information, and the locations along the route. 2.The method of claim 1, wherein the wireless message characteristicsinclude one or more of received signal strengths of the wirelessmessages, receipt of messages communicated at known times, missedwireless messages of the wireless messages, or corrupted wirelessmessages of the wireless messages.
 3. The method of claim 1, wherein thewireless messages include distributed power messages wirelesslycommunicated between the first vehicles in the one or more first vehiclesystems during remote control of one or more remote vehicles of thefirst vehicles by one or more lead vehicles of the first vehicles. 4.The method of claim 1, wherein the consist configuration informationincludes one or more of a size of the one or more vehicle systems orrelative positions of the vehicles in the one or more first vehiclesystems during the movement of the one or more first vehicle systemsalong the route.
 5. The method of claim 1, wherein the signalpropagation profile includes a spatial relationship between the wirelessmessage characteristics of the wireless messages and the locations alongthe route.
 6. The method of claim 1, further comprising creating a tripplan for an upcoming trip of a second vehicle system based on the signalpropagation profile, the trip plan designating operational settings ofthe second vehicle system at one or more different times or distancesalong the route and that are to be wirelessly communicated from a leadvehicle of the second vehicle system to one or more remote vehicles ofthe second vehicle system for wireless control of the one or more remotevehicles according to the trip plan, wherein the trip plan is createdbased on the signal propagation profile such that the operationalsettings that are designated in the trip plan for the one or more remotevehicles do not change during movement of the second vehicle systemthrough one or more segments of the route based on the signalpropagation profile.
 7. The method of claim 1, further comprising:creating a trip plan for an upcoming trip of a second vehicle systembased on the signal propagation profile, the trip plan designatingoperational settings of the second vehicle system at one or moredifferent times or distances along the route and that are to bewirelessly communicated from a lead vehicle of the second vehicle systemto one or more remote vehicles of the second vehicle system for wirelesscontrol of the one or more remote vehicles according to the trip plan;identifying one or more upcoming segments of the route associated withan inability to wirelessly communicate between the lead vehicle and theone or more remote vehicles based on the wireless messagecharacteristics associated with the one or more upcoming segments of theroute; and wirelessly communicating scheduled commands from the leadvehicle to the one or more remote vehicles prior to the one or moreremote vehicles reaching the one or more upcoming segments, thescheduled commands including the operational settings designated by thetrip plan for one or more locations within the one or more upcomingsegments of the route.
 8. The method of claim 1, further comprisingidentifying one or more second vehicles to be included in a secondvehicle system for travel along the route during an upcoming trip of thesecond vehicle system based on the signal propagation profile.
 9. Themethod of claim 1, further comprising generating one or more warnings toan operator of a second vehicle system moving along the route of one ormore upcoming segments of the route where wireless communicationsbetween a lead vehicle and one or more remote vehicles of the secondvehicle system are degraded based on the signal propagation profile. 10.The method of claim 1, further comprising: monitoring additionalwireless message characteristics of additional wireless messagescommunicated between a lead vehicle and one or more remote vehicles in asecond vehicle system during movement of the second vehicle system alongthe route; and generating a warning indicative of a fault in acommunication system of the second vehicle system based on a comparisonbetween the additional wireless message characteristics for the secondvehicle system and the signal propagation profile.
 11. A systemcomprising: one or more processors configured to determine wirelessmessage characteristics of wireless messages communicated with firstvehicles in one or more first vehicle systems and locations along aroute where the wireless message characteristics were determined, thewireless message characteristics and the locations determined duringmovement of the one or more first vehicle systems along a route, the oneor more processors also are configured to obtain consist configurationinformation about the one or more first vehicle systems, and todetermine a signal propagation profile based on the wireless messagecharacteristics, the locations where the wireless messagecharacteristics were determined, and the consist configurationinformation, wherein the signal propagation profile represents one ormore relationships between the wireless message characteristics, theconsist configuration information, and the locations along the route.12. The system of claim 11, wherein the wireless message characteristicsinclude one or more of received signal strengths of the wirelessmessages, receipt of messages communicated at known times, missedwireless messages of the wireless messages, or corrupted wirelessmessages of the wireless messages.
 13. The system of claim 11, whereinthe wireless messages include distributed power messages that werewirelessly communicated between the first vehicles in the one or morefirst vehicle systems during remote control of one or more remotevehicles of the first vehicles by one or more lead vehicles of the firstvehicles.
 14. The system of claim 11, wherein the consist configurationinformation includes one or more of a size of the one or more vehiclesystems or relative positions of the vehicles in the one or more firstvehicle systems during the movement of the one or more first vehiclesystems along the route.
 15. The system of claim 11, wherein the one ormore processors are configured to identify one or more second vehiclesto be included in a second vehicle system for travel along the routeduring an upcoming trip of the second vehicle system based on the signalpropagation profile.
 16. A system comprising: a control unit configuredto be disposed onboard a first vehicle system having plural vehicles fortraveling together along a route, the control unit configured to obtaina signal propagation profile for the route that is representative ofwireless message characteristics for one or more second vehicle systems,consist configuration information of the one or more second vehiclesystems, and locations along the route where the wireless messagecharacteristics were measured during previous travel of the one or moresecond vehicle systems along the route, wherein the control unit isconfigured to compare consist configuration information of the firstvehicle system with the consist configuration information of the one ormore second vehicle systems in the signal propagation profile todetermine a spatial relationship between the wireless messagecharacteristics of the one or more second vehicle systems and thelocations along the route.
 17. The system of claim 16, wherein theconsist configuration information of the first vehicle system includesone or more of a size of the first vehicle system or relative positionsof the vehicles in the first vehicle system.
 18. The system of claim 16,further comprising an energy management system configured to create atrip plan for a trip of the first vehicle system along the route basedon the signal propagation profile, the trip plan designating operationalsettings of the first vehicle system at one or more different times ordistances along the route and that are to be wirelessly communicatedbetween the vehicles of the first vehicle system for wireless control ofone or more of the vehicles according to the trip plan.
 19. The systemof claim 18, wherein the energy management system is configured tocreate the trip plan based on the signal propagation profile such thatthe operational settings that are designated in the trip plan for theone or more vehicles in the first vehicle system do not change duringmovement of the first vehicle system through one or more segments of theroute based on the spatial relationship between the wireless messagecharacteristics of the one or more second vehicle systems and thelocations along the route.
 20. The system of claim 18, wherein thecontrol unit is configured to identify one or more upcoming segments ofthe route associated with an inability to wirelessly communicate withone or more of the vehicles in the first vehicle system based on thewireless message characteristics associated with the one or moreupcoming segments of the route from the spatial relationship between thewireless message characteristics of the one or more second vehiclesystems and the locations along the route, the control unit alsoconfigured to communicate scheduled commands to the one or more vehiclesprior to the one or more vehicles reaching the one or more upcomingsegments, the scheduled commands including the operational settingsdesignated by the trip plan for one or more locations within the one ormore upcoming segments of the route.
 21. The system of claim 18, whereinthe control unit is configured to generate one or more warnings to anoperator of the first vehicle system moving along the route of one ormore upcoming segments of the route where wireless communicationsbetween the vehicles of the first vehicle system are predicted to bedegraded based on the spatial relationship between the wireless messagecharacteristics of the one or more second vehicle systems and thelocations along the route.
 22. The system of claim 18, wherein thecontrol unit is configured to monitor additional wireless messagecharacteristics of additional wireless communications between thevehicles during movement of the first vehicle system along the route andto generate a warning indicative of a fault in a communication system ofthe first vehicle system based on a comparison between the additionalwireless message characteristics for the first vehicle system and thespatial relationship between the wireless message characteristics of theone or more second vehicle systems and the locations along the route.